Add PF2e attack effects, ability frequency, and perception details

Show inline on-hit effects on attack lines (e.g., "plus Grab"), frequency
limits on abilities (e.g., "(1/day)"), and perception details text alongside
senses. Strip redundant frequency lines from Foundry descriptions.

Also add resilient PF2e source fetching: batched requests with retry,
graceful handling of ad-blocker-blocked creature files (partial success
with toast warning and re-fetch prompt for missing creatures).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/web/src/components/stat-block-parts.tsx

@@ -141,6 +141,7 @@ export function TraitEntry({ trait }: Readonly<{ trait: TraitBlock }>) {
 					</>
 				) : null}
 			</span>
+			{trait.frequency ? ` (${trait.frequency})` : null}
 			{trait.trigger ? (
 				<>
 					{" "}